﻿using System;
using System.Collections.Generic;
using System.Text;

namespace ConsoleApp2
{/// <summary>
///不能被实例化，全为静态成员
/// </summary>
    public static class Student5
    {
        public static string ClassName="软件二班";
        public static string Major="software";
        public static void Play(this string str) 
        {
            Console.WriteLine(str);
        }
    }
}
